1,8-Naphthyridone-3-carboxyl is the core structure of several on-market antibacterial drugs. It has prompted significant interest from the synthetic community. Here, we report a practical synthesis of diversely functionalized 1,8-naphthyridone-3-carboxylic acid derivatives starting from readily available and inexpensive nicotinic acid derivatives. All key steps have been optimized. Furthermore, the usefulness of this protocol has been exemplified by the first synthesis of amfonelic acid.

中文翻译：

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1,8-萘啶酮-3-羧酸衍生物的获取及其在氨苯酸合成中的应用

1,8-萘啶酮-3-羧基是多种市售抗菌药物的核心结构。它引起了合成界的极大兴趣。在这里，我们报道了一种以容易获得且廉价的烟酸衍生物为原料的多官能化1,8-萘啶酮-3-羧酸衍生物的实用合成方法。所有关键步骤均已优化。此外，该方案的有用性已通过氨苯酸的首次合成得到例证。